Marine vessel.



No. 812,604. PATENTED FEB. 13, 1906. J. J. SITZLBR.

MARINE VESSEL.

APPLIOATION IILED APR.14,1906.

' MINESSES. INVENTOI? 09402; M f; ffiizlez- I hZ/MWQ M ATTORNEYS JOHN J. SITZLER, OF NEW YORK, N. Y.

Y MARINE VESSEL.

Specification of Letters Patent.

Patented Feb. 13, 1906.

Application filed April 14,1905. Serial No. 265,493.

To all whom it may concern.-

Be it known that I, J OHN J. SITZLER, a citizen of the United States, and a resident of the city of New York, borou h of Brookl in the county of Kings an; State of ew York, have invented a new and Improved Marine Vessel, of which the following is a full, clear, and-exact description.

The invention relates especially to propulsion of marine vessels, the object being to reduce the displacement of the vessel to a minimum, so as to reduce the resistance to propulsion, and 'to produce a more efficient propeller than that commonly em loyed. I attain these ends by certain pecu iar features of construction and arrangement of parts, all of which will be fully brought out hereinafter and. pointed out in the claims.

Reference is to be had to the accompanying drawin s, which-illustrate as an example the pre erred manner of embodying my invention, in which drawings like characters of reference indicate like parts in the several views, and inwhich- Fi ure 1 is a bottom plan view of a marine vesse havin two sets of ropelling devices. Fig. 2 is a si e elevation o the same. Fig. 3 is a detail view showin the forin of the screwpropeller employed. Fig. 4 is an end view of the parts shown in Fig. 3, and Figs. 5 and 6 are respectively sections on the lines 5 5 and 6 6 of Fig. 3.

The hull 10 of the vessel is formed on its bottom with two pockets 11, which are intended to be submerged and which contain the crank-shafts of the two en ines which drive the vessel. The crank-sha ts of the engine are connected by couplings (indicated by broken lines 12 in Fig. 2) to the shafts 14 of the forward and after propellers. The shafts 14 project from the forward ends of the pockets 11 to the bow of the boat and from the after ends of the pockets to the stern, and said shafts are carried in suitable bearings 15 and 16, as shown. As indicated by the broken lines in Fig. 2, the bearings 15 have oil-ducts 17 therein, which permit lubricating the shafts from within the hull of the boat. Between each set of propellers a divisional wall or keel 18 is located, the keels running fore and aft and the aft keel carrying a rudder 19, as shown. At their front extremities the shafts 14 have conical heads 20, which serve to break the water from the bearings 16 adjacent thereto.

The propellers are in the form of continuous screws 21, each screw havin two blades and said, blades leaping or over anging the shaft, as illustrated in Figs. 1 and 2. This overhanging of the blades is also illustrated at the point 21 in Fig. 3. Such form gives' the propeller the greatest efliciency. The forward propellers are provided with cones 21 near the pockets 11 forming the shafts of the propellers. Said cones serve to open the water ahead of the pocket 11 and to reduce resistance against the pocket. The propellers 21 may be formed with their blades in integral lengths, as indicated in Figs. 1 and 2, or they may be formed of a number of sections, as indicated in Figs. 3 to 6, these sections being strung on the shaft and fastened together with their side edges in contact, so

as to form the continuous screw shown in F' s. 1 and 2.

hile I have shown the vessel provided with two pockets 11 and two sets of propelling-screws, I desire it understood that the vessel could be constructed with but one pocket and a single set of fore and aft propellers. In this case the divisional keels 18 would also be dispensed with and the single pocket would .be located in the transverse center of the hull. i

Having thus described the preferred form of my invention, what I claim as new, and desire to secure by Letters Patent, is

1. A marine vessel having a hull with a pocket projecting downward from its bottom below the floor-line of the hull, said pocket being adapted to carry the engine crankshaft, two propelling-screws projecting fore and aft and extending respectively from the ends of the pocket to the bow and stern, said screws having shafts pro'ecting into the ocket and the shaft of the orward propeller being tapered from the pocket forward, for the purpose specified, means in the pocket for connecting the shafts with the crankshaft, a conical head at the forward end of the forward screw and means for revolubly mounting the screws, said means for mount ing the screws comprising bearings at the bow and stem and an additional bearing for each shaft located intermediate the pocket and the bow and stem bearings respectively.

2. A marine vessel having a hull with two pockets intermediate the length of the hull said pockets being spaced from each other and projecting below the floor-line of the hull and each being adapted to carry the engine crank shafts, propelling screws projecting fore and aft from each pocket, the screws having shafts extending into the pockets a nd the shafts of the forward screws tapering from the pockets forward, for the purpose specified, means in the pockets connecting the propeller shafts with the crankshafts means for revolubly mounting the screws and keels located between the members of the 10 forward and after pairs of screws.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JOHN J. SITZLER. Witnesses: J. C. LANE,

CARL H. LISBERY. 

